Alternatives to the gradient in optimal transfer line buffer allocation

Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, Operations Research Center, 2004.Includes bibliographical references (p. 113-114).This thesis describes several directions to replace the gradient in James Schor's gradient algorithm to solve the dual problem. The alternative directions are: the variance and standard deviation of buffer levels, the deviation of the average buffer level from half-full, the difference between probability of starvation and blocking, and the difference between the production rate upstream and downstream of a buffer. The objective of the new algorithms is to achieve the final production rate of the dual problem faster than the gradient. The decomposition method is used to evaluate the production rates and average buffer levels. We find that the new algorithms work better in lines with no bottlenecks. The variance and standard deviation algorithms work very well in most cases. We also include an algorithm to generate realistic line parameters. This algorithm generate realistic line parameters based on realistic constraints set on them. This algorithm does not involve filtering and is fast and reliable.by Ketty Tanizar.S.M

Shopping Goals, Goal Concreteness, and Conditional Coupons

assistance. The authors are especially grateful to Mr. Frank La Verde, Mr. Marc Semon, and all staff of La Verde’s Market for their kind support and co-operation, and to the Editor, Dawn Iacobucci, the Associate Editor, and three reviewers for their insightful comments and suggestions. 3 We propose a two-stage model to describe the increasing concreteness of consumers ’ goals during the shopping process, testing the model through a series of field experiments at a convenience store. Using a number of different process measures (experiment 1), we first established that consumers are less certain of their shopping goals and construe products in less concrete terms when they are in the first (vs. second) stage of the shopping process. The results of experiments 2 and 3 next demonstrate that goal-evoking marketing promotions (e.g. conditional coupons) are more effective in influencing consumers ’ spending when consumers’ goals are less concrete. 4 Accumulating evidence points to the pivotal role of goals in our daily lives, providing us with a sense of direction and clarity for our actions, and influencing the way we think and behave (Gollwitzer 1990; Kruglanski et. al. 2002; Kunda 1990; Locke and Latham 1990). It has bee